Mold for forming all plastic shoes



Mafch 7, w50 J. J. BOOTH 2,499,565

MOLD FOR FORMING ALL PLASTIC SHOES Filed May 15, 1946 QZC//C/aaf# INVENToR.

Patented Mar. 7, 1950 UNITED STATES PATENT OFFICE IVIOLD FOR FORMING ALL PLASTIC SHOES Jack J. Booth, Dallas, Tex.

Application May 15, 194.6, Serial No. 669,989

1 Claim. 1

This invention relates to the shoemaking art l and has as its principal object to provide for the manufacture of a shoe formed or molded of a suitable plastic material or materials in a single piece or unitary structure, possessing desirable texture, plasticity, flexibility, color and finish, such as described in my application Serial No. 556,183, allowed August 24, 1948, now Patent Number 2,470,089. l

To attain these desirable characteristics, the invention provides as a principal object a mold of suitable design, permitting of the introduction thereinto at suitable places of the requisite quantities of materials, which will unite and bond into a nished, one piece shoe, as the molding and curing processes are developed, the finished product to possess the desired characteristics indicated.

Another object of the invention is to provide an article of new manufacture, particularly an all plastic shoe, especially a shoe of all plastic material having means produced by a mold for insulating the wearers foot against heat irritation or lack of ventilation by incorporation in the mold certain prerequisites for creating in the nished article a multiplicity of minute recessions or grooves, preferably running lengthwise of the sole, heel and toe combined `with transverse, interconnecting recessions or grooves which extend at least the width of the interior of the sole of the shoe.

Features of accomplishment are pointed out in the following description together with the ac companying drawings, in which:

Figure 1 is a schematic end view of a mold and injection apparatus in vertical section showing the manner in which a one piece shoe is produced.

Figure 2 is a plan view, partly in section, taken on line 2--2 of Figure 1.

Figure 3 is a side elevation of the inner mold form showing a section of shoe thereon.

Figure 4 is a plan view of a grooved sole of a shoe produced from the mold of the invention, and

Figure 5'is a magnied end sectional view of the sole as shown in Figure 4.

In the several views, like references indicate similar elements, in which I0 is a conventional apparatus for injecting plastic material at desired temperatures and suitable pressures through ports or nozzles il into suitable receiving ports I2 of my mold I3, while I4 is a structure for supporting mold I3 in such a manner that when the mold is brought into operating relation with the injection apparatus I0 the discharge nozzles Il will be brought into sealed registry with receiving ports i2 of the mold. Any suitable means, such as a hydraulic ram or pressure apparatus (not shown) may be used to bring and retain the mold and injection apparatus into operative relation. One part of the outer mold I3 is rigidly attached to support I 4 and the other part is guided into operative position by guide pins I5 received by openings I 6 in respective parts of the outer mold I3. The outer mold I3 is provided with a cavity I'I in the form of the outer surface of the shoe to presently be molded and is adapted Y to receive the inner form I8 in the shape of the inner surface of the desired .shoe to be formed. Inner form I8 is provided with a shank I9 and an extension 20 for retaining the respective mold parts in desired relation during necessary manipulation, to facilitate which extension 20 is pro-.- vided with slotted openings 2I for receiving studs 22 threadedly engaging support I 4. The mold parts I3 are provided With guide and retaining pms 22a to be received by suitable openings in the shank I9 of the inner form I8 as the assembled mold is brought into position. The space or cavity thus secured is the exact shape and form to provide the desired thickness of the iinished shoe in all its parts.

To further facilitate manipulation of the parts, compression springs 23 are operatively positioned between support I4 and extension 20 so as to be compressed, as parts of outer mold I3 are brought together about the inner mold I8 and operatively with the injection apparatus and exert a presr sure tending to effect separation of the parts of mold I3, as the molding cycle is completed. For maintaining desired working temperatures in the molds they are, or may be provided, with openings 24 for suitable media to be circulated by conventional means, which media are employed at temperatures necessary to eiect proper tem# perature control in the molds.

The mold I8 may be provided with projections 25, which may be used as spacers for the mold parts, and to create desired artistic designs on the finished shoe, as well as ventilation openings at desired positions in the shoe structure.

Space at the juncture of the mold parts usually will be found adequate for escape of entrapped air from the mold cavity. However, auxiliary openings 26 are provided when desired to facilitate the flow of materials being introduced into the mold.

While only two openings I2 are shown for receiving the material into the mold. it is obvious that' any number' may be provided to effect proper iiow of materials of desired or varied texture, plasticity, porosity, color or the like to make a completed shoe having all desired characteristics. The operation of forming a shoe is readily performed by closing the mold and inducing the proper temperature by means of the circulating medium and bringing the molds into position to receive the plastic materials of the desired consistency, color, etc. and of proper quantities, and at the proper number and positions from the injection apparatus to form the shoe, and maintaining these materials in the mold for such period or cycle of time, and at temperatures and pressures required to 'secure the bonding and curing thereof into a shoe vof one piece.

It will be readily understood by those skilled in the art that as materials vary in characteristics or properties, adjustments and variations of the several details of the apparatus may be required to leffect the desired results. These `variations may include temperatures, pressures, number and location of introduction points for the material as well l'as escape'vents vfor air and overflow of material and time cycle vof operations.

It will readily occur to those skilled inthe art vthat reinforcements-or .inserts such .as in the arch, heel or toe, may be incorporated in the shoe by positioning these elements in the mold cavityso that the material flows .about them in the manner vdesired and cures with vsuch elements fin place.

Moreover, as illustrated in Figures 14 and, .the inner 'soleA as well as the inner side surfaces of the shoe may be providedwith minute grooves a for ventilation purposes as produced `bythemold extending both longitudinally and transversely of the sole.

Also the vdesired nishor design vmay be yprovided `on any part of the shoe by the nish or design vof the corresponding .mold surface.

When the molding roperation is completed the pressure is released on thezparts of the outer mold |3.and the compressed springs23 .urge the mold I8 and a part of the vmold 'lf3 away :from the other part of .the mold I3, thus exposing a-portion of the finished shoe. The remaining portion of the mold vI3 is'theriremoved'and'the'finished plastic vsl'ioesimanipulated oi of .its inner form I8 by handor other suitable means.

Most materials suitable for manufacture of plastic shoes will possess Asufficient .elasticity to permit of ready removal from the Ymold 1.8 vand projections l25. 'Where .other materials are used I may provide a collapsible inner mold lor'provide for retractible projections 25 to facilitate removal of the finished shoe from the mold.

Manifestly, the construction as shown and described is capable of some modification and such modification as may be construed to fall within the scope and meaning of the appended claim is also considered to be within the spirit and intent of the invention.

What is claimed is:

In a mold for forming shoes .of lplastic materlial :having yintegral soles, heels .and uppers, comprising in combination a 'fixed mold member provided with a cavity in one face corresponding to the outer surface of half the Width of the shoe through said sole, heel, and upper, said member having a plurality of feeding ports communieating with the cavity adapted to register with plastic'inj'ec'tin'g apparatus; a support; from which saidfmold member depends, a movable mold member having guide pins slidable in openings in the fixed member and provided with a complementary i cavity .inits face `adjacent Ythe fixed lmember corresponding to the outer surface of the .other half of the width of .the shoe through said sole, heel, and upper; each .of saidmold members having .huid-circulating vducts extending ,therethrough, an inner mold member having ashank on the support and slidable towards vand vaway from said fixed mold member and having a forming surface fadapted to be vdisposed within the cavities of said fixed and vmovable `mold members and spaced therefrom 4to .dene the shape and .thickness of the upper and sole; minute longitudinal rand :transverse ridges in closely spaced relationshipori .the -undersurface i of said inner mold lmember ;and, `compression Asprings interposed ibetween the .shank vof .said inner mold member and said support to exert yieldingpressure tending to .effect lateral .separation vof ,the

'40 members .ofthe mold.

.JACK `J. BOOTH.

:REFERENCES `CITED 'The ffollowing references are of record in the 

